High-speed pulse reception system



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2 Sheefcs-Sheet l w w a I R D. L. HINGS HIGH-SPEED PULSE RECEPTION SYSTEM Dec. 5, 1950 Filed Aug. 6, 1945 GENERATOR RESPONSIVE DEVICE CURRENT INVENTOR DM Q 4 ATToRNa M Dec. 5, 1950 H s 2,532,667

HIGH-SPEED PULSE RECEPTION SYSTEM Filed Aug. 6, 1945 2 Sheets-Sheet 2 wmu w INVENTOR EJY ATT 0 ms Patented Dec. 5, 1950 PATENT QEFICE.

HIGH-SHRED PULSE RECEPTION SYSTEM ApplicationAugustifi, 1945, Serial No. 6ll9.,26l; Inflariada July 20, 1945 (Cl. ZEN-20) 3 Claims.

This application constitutes an improvement in my application Serial No, 609,260 fi 1ed" the sixth day of August 1945 for Pulse Reception System and executed concurrently herewith.

My inventionrelatestoa. pulse reception sysemcand more particularlyto a pulse reception system having both pulsed continuous waves and interference waves between which discrimi nation is made for the. purpose of establishing a. control circuitto goyerna current re ponsive device, and which gives, a linear respons at. high frequencies of: theinterference waves,

An object of my invention is the provision in a pulse reception systemw which avoids the re-. quirement of rectifyingthe energies inorder that hey m shth r her a t r t d n heir sme t: tude.

Ano her qbicctof my en ion is the li v r sion of limiting the value of the amplitude f, theinter e enqe ne es y means of. asiiufir wav a fier.

ot er jec of my nve t on is to. pro e for giving relatively largedirect current output wher y the utrutmay be; coupl d oopera dir ct a; urrent re po ive device.

Ano her. objector my nve o s he. provir 0. n. a uls ecep sys emhi h, oid se. of, nduct ve compon s:

n h r q ie t. of y nv nti s he mov e 510.11 a, ce t n tem. ha in th ulsed on ous Waves d. t f qe Wav s 1 1 1 w th mean dur n he. s acer ter a for utilizing the energy from the interference ve a d o e tr ii ns oth he, pul ed con: tinuous waves and the interference waves dure ing the marker intervals.

Another obiectot my invention. is the provi sion in a, pulse receptipn system of injecting generated interference waves over and above thawinherent spurious interference waves, whereby an increased amgunt of energy is available during the spacer intervals for utilization as a means of control to. govern. a current responsive device which generates: a secondary pulsed continuous wave which has substantially the same time constants as the primary pulsed continuous waves.

Another; object; of my invention is the provision in a pulse reception system of means for injecting energy into the system; which is available for control purposes during the spacer intervals of the pulsed continuous wave;

Another object of my invention is the provision in a pulse reception system which short circ t he sedp qn mius aves uring he 21 ma k r n e a n w ieh r de purge. of control; energy during the spacer intervals.

Another object of my inventionis to inject, into a pulse receptionsystern, interference en; ergies having a larger magnitude than that of the spurious interference energies.

Other objects and a fuller understanding of m n n ma e has from e, qllg n description and claims, taken conjunction with the accompanying drawings, in which;

Figure 1 represents a diagrammatic View of a pulse reception system embodying the features of my inyention;

Figure 2 is a view ofa pulsedcontinuous wave which is shown as being free Of, all interference waves and is shown as having a fading amplitude component.

Figure 3 is a view of a spurious interference wave which is present in normal atmospheric reception.

Figure l shows a view of a discha ge interference wave, having a random peakedenvelope, which may be injected into my pulse reception system.

Figure 5 shows a view of the combination en ergy wave comprising both the spurious interference energies and the injected interference energies, with the amplitude of the energies limited and being discontinuous through the marker period.

Figurefi is a view of, an amplifier square wave produced from the energy wave of Figure 5,

' Figure '7 is a view of the amplitude 'waye in Figure 6, after the frequency of the wave Figure 6 has been doubled and the amplitude of the energies limited to a predetermined level.

Figure 8 isayiew representing an energy wave produced by filtering the wave of Figure 7 Figure 9 is a pulsed continuous wave gen; erated by a, secondary source and governed by a current responsive deyicein response to the en: rs v btained, r g h a r nt s fr m he, n erfe ence w v Figure 10 shows a modified pulsed continuous wave, generated from the secondary source. and having an inverse time constant with respect to Figure 9, of the same time constant as Figure 2 which shows the primary pulsed. continuous WW6- With reference to Figure 1 of the drawing) the reference character it represents a transformer ar s a P ima winding 7 ptfid 2 3 3 uls d cont n us W ves which m s e -Q P pu sed ra m t: ion of t nc s h], fo ex m e s a ulse co tin u v mulsi ie in the operation of a teleprinter or other device. A condenser i2 is connected across the primary winding I! and the two constitute a tuned circuit which may be tuned substantially to resonance at a frequency equal to the frequency of the incoming carrier waves.

My invention preferably provides for injecting interference waves into the transformer circuit, whereby the transformer delivers both pulsed continuous waves and injected interfereme waves. The injection of the interference waves into the pulsed continuous waves may be done by employing an interference wave generator 13, which may be connected to the transformer circuit by a switch l5. When the switch closed, the interference waves injectedinto the pulsed continuous wave system have a random discharge wave envelope, as shown in Figure 4. The construction and arrangement of the interference wave generator is may be substantially the same as that shown in my pending application, executed concurrentsy herewith, entitled Discharge Wave Generator, Serial No. 609,259, filed August 6, 1945, now Patent No. 2,468,754, granted May 3, 1949.

Figure 2 may represent a pure pulsed continuous wave which is excited in the transformer Ill, without the presence of the spurious interference waves which exist in reception under normal atmospheric conditions. Figure 3 shows a representation of a spurious interference wave as may be found in reception. In actual operation, the incoming energy received from the pulsed continuous wave transmitter would be a combination of Figures 2 and 3. a representation of an interference wave as delevered by the interference wave generator l3.

In actual operation, the wave energies excited in the secondary winding E6 of the transformer would be a combination of the waves shown in Figures 2, 3 and 4. In my invention, the injected interference energies preferably have a larger magnitude than that of the spurious interference energies. A condenser I! is connected across the secondary winding I5 and provides in combination therewith a tuned circuit which may be tuned substantially to resonance at a frequency substantially equal to the frequency of the incoming pu sed continuous wav s. The energy delivered by the secondary winding i 6 and the condenser I! is detected and limited by a duo-diode rectifier I8 comprising two plates l9 and 2!) and two cathodes 2| and 22. The plate !9 and the cathode 22 are connected to the upper terminal 23 of the secondary winding it. The cathode 2! is connected to ground and to the lower terminal 24 of the secondary winding I 6 tlgrough a high-frequency by-pass condenser A battery 26 is connected between the plate 20 and the cathode 2!. The plate l9 and the cathode 2| constitute a part of the detector circuit which comprises the resonant circuit l6 and l! and the fixed resistor 21 and the adiustable resistor 28. The fixed resistor 2 in combination with the condensers 25 and 29 constitutes a high-frequency filter and the adiustable resistor 28 constitutes a detector load resistance.

In actual operation, the plate l9 and the cathode 2! pass current from the secondary winding [6 until the voltage of the detector circuit reaches a value equal to the voltage of the battery 26, at which point the energy from the secondary winding 15 is conducted to ground through a circuit including the cathode 22, the

Figure 4 shows 3;

plate 20 and the battery 26. In my invention, the potential of the battery 28 and the design of the detector circuit is such that the voltage generated in the detector circuit resulting from a detection of the pulsed continuous wave is always greater than the voltage of the battery 26, whereby during the marker intervals the energy of the secondary winding it of the transformer below the effective battery bias is conducted to the load resistor 28 and the energy which is above the effective battery bias is neutralized. Thus, under the above condition, the pulsed continuous waves during the marker intervals, as Well as the spurious interference waves and the injected interference waves, are suppressed and prevented from flowing in the detector circuit. This condition is similar to that shown in Figure 5 which shows the voltage across the tuned circuit l 6-! 1. However, the design of the detector circuit and the voltage of the battery 25 is such that a major portion of the energies from the spurious interference waves and the injected interference waves is permitted to flow in the detector circuit such as would be shown in Figure 5 were the lower half of the wave removed, the high peaked random amplitudes being cut off. In other words, the detector circuit is such as to limit the amplitude of the detection of the spurious interference waves and the injected interference waves. The random peaked amplitudes of the spurious peaks in my invention may be many times greater'than the amplitude of the pulsed continuous waves, but they are limited by the action of the duo-diode rectifier H3. The same is true with respect to the amplitudes of the injected interference waves. Even though the amplitudes of the spurious interference waves and the injected interference waves are limited to a predetermined value, yet there are a multitude of tiny spaces therebetween, which envelope may be detected below the level of the predetermined value to which they are limited. To further explain the operation of this part of my circuit, I offer the following theory, but do not intend to be bound by the consequences of any theory: During the spacer intervals, since the envelope of the interference wave will periodically, at an audio frequency rate, drop to zero or to a magnitude less than that of the predetermined level of the battery bias, neutralization will not occur at these periods, and therefore an audio frequency voltage will appear across the load resistor 28, to be passed to the next stage. Now during the marker intervals, the voltage of the incoming signal, that is, the pulsed continuous wave, being a continuous wave that has an envelope alwa s greater in magnitude than the effective battery bias, dominates the tuned circuit 16-57 to cause the positive ha f cycles passed by the diode elements l9 and 2| to fully occupy the diode rectifying cycle. Therefore, the filtering action of the high frequency filter 25, 29 and 21 smooths out the high frequency half cycles to effectively produce a direct current component across the load resistor 28, as governed by the effective battery bias. The rectification of the negative half cycles in excess of the battery bias neutralizes that portion of the positive half cyces in excess of the battery potential in the filter 252'l-29, thereby leaving only the direct current voltage from the diode iii-2| at a potential substantially proportional to the effective battery bias across the load resistor 28. This neutralization of the high asse sor frequency cycles means that all alternating potentials are neutralized andtherefore no envelope exists. Thus neutralization of the high frequency cycles may also be considered as neutralization of the envelope, which means that nosignal is passed tothe-next Stageduring the marker interval.

The next process in my pulse reception sys tem is to-amplif-y the detected energy waves, and, as illustrated, I providean amplifier 31 for this purpose. The amplifier 3"? may compriseaplate 38, a cathode 39 and agrid 48. With the switch t5- closed, which is the condition when interference waves areinjected into the system, the detected energy from resistor as: of? the detector circuit is coupled directly to the grid? id. of? the amplifier tube i'l'by-acondenser 35 The resistor 32 is the grid resistor for the grid. at. and; the resistor M is the cathode biasing resistor tor the. cathode 39. The condenser 42 is a by-pass for the cathode 35 to ground. The wave which appears in the cathode platecircuit of the amplifiat it? may be represented as similar to the envelope of the wave of Figure 5, although in actual practice the amplitude may be relatively greater than that shown in Figure 5. The plate 38 of the amplifier Si is connected to the positive side of the high voltage source as: through. a plate load resistor 4-6. The amplifier output from the plate 3-8 of the amplifier tube 3? is coupled through a coupling condenser 55 to a square waye amplifier tube 18 which comprises two plates as and 5t, two cathodes 5 l. and 5t and two grids 53 and 5 L The grid 53 is: connected to the condenser ti -and to ground through. the resistor All. The cathodes 5i and 52 are joined together and both are connected to ground through a cathode biasing resistor 55. The plate 49 is directly connected to the high voltage source 59. The plate 58 is connected to the high voltage source 59 through a plate load resistor Eii. The output of the square wave amplifier tube as appears between the plate 56 and ground, which is shown in the Figure 6. The cathode M is positive with respect to ground and, inasmuch as the grid is connected to ground, it is more negative than the cathode 5i.

In operation of the tube 48, when there is no wave excitation from the interference energies applied to the grid 53, both the cathode-to-plate circuits of the tube pass substantially the same amount of dlect current. Nhen the grid 53 is excited by the positive cycle of the incoming interference waves, the excitation on the grid 53 more current to fiow from the cathode 5| and the plate as and thus the cathode hi and the plate 59 function as an amplifier. The increased flow of the current through the cathode ii! and the plate so causes the cathode 5! to swing more positive and causes the current which is flowing between the cathode 52 and the plate at to be cut off at a predetermined value due to the increased bias of the cathode 52 with respect to the grid 54 and thereby produces a square wave having a predetermined amplitude. As the grid 53 is excited with energies irom the negative cycle of the incoming interference energies, then the current which flows between the cathode 5| and the plate as is cut oil at a predetermined value and, when this out-ofi situation is effected between the cathode 5i and the plate 45, the oathode becomes inoperative, with. the result that the current fiow between the cathode 52 and the plate at is constant, which produces a square wave for the opposite cycle. Thus, the cathode 52 and till the plate Ell in conjunction with the cathode. 51': and the plate Q9 operate as a square waveamplifier for delivering an alternating current square wave. The amplitude of the alternating current squarewave is determined by the am-. plification factor of the tube. This square wave energy is delivered to an inverter tube B l through a conductor 5% and a coupling condenser 51. The inverter tube E34 comprises a plate 65-, a cathode 65 and a grid blwhich is connected to the condenser 51. The plate 65 is connected to the high voltage source 59 through a plate load resistor 58. The cathode E55 is connected to ground through a cathode biasing resistor l2 and acathode load resistor 68. The grid 61 is. connected to a point E 3 intermediate the two resistors 53 and i2 through a grid resistor 69. The output from the inverter tube 64. is applied to the coupling condensers it and H and gives a push-pull output. The operation of the inverter tube (it is such as to convert the energy delivered thereto into a full-wave source above ground through the push-pull output. The tube 84 may be characterized as. having a push-pull output, whereby the output energy may be suitable for full-wave rectification. The output fullwave energy from the tube ficis rectified by means of a rectifier tube '54 which comprises two: plates 15 and 7S and two cathodes Ti and E8. The resistors. 19 and are plate isolating resistors for the plates l'ii and respectively. The fullwave rectified output from the rectifier tube 1.4 may be filtered b means of a resistor M and a condenser at. The output is shown as being diagrammatically delivered to a current respon stve device: it: which may be any suitable device for generating a secondary pulsed wave and functioning as a method of control for giving a secondary pulsed continuous wave which has substantially the inverse time constants as the primary pulsed continuous waves as shown by the secondary wave in Figure 9 or which has substantially the same time constants as shown in Figure 10.

The subjection of the energy waves as shown in Figure 6 upon the inverter tube 64 and the rectifier tube M produces in the output of the rectifier tube '14 energy waves such as shown in Figure 7. The resistor BI and the condenser 82 filter the energy waves of Figure 7 and produce a relatively pure wave output as shown in Figure 8, which wave is applied to the current responsive device 83 for operating same.

It is noted in the arrangement of the circuit in Figure 1 that I employed no inductive device which slows up the speed. of operation of my circuit. In fact, the various stages of the circuit are coupled by means of resistance coupling, which permits a truer response for higher-frequency interference waves.

Although I have shown and described my invention with a certain degree of particularity, it is understood that changes may be made therein without departing from the spirit of the invention which are included within the scope of the claims hereinafter set forth.

I claim as my invention:

1. In a pulsed continuous wave reception system having on and off periods producing alternate spacer and marker intervals, means for producing interference waves having a component of frequency lower than said continuous wave in the pulsed continuous wave reception system, detector means adapted to receive both continuous Wave and interference energy and including means during the marker intervals for neutralizing the pulsed continuous Waves and the inter ference waves and means during the spacer intervals for detecting and limiting the interference waves having a voltage exceeding a first pre determined value, means for amplifying the de tected and limited interference Waves, a square wave amplifier for amplifying and limiting the interference waves having a second voltage exceeding a predetermined value, inverter tube means having a push-pull output circuit for rendering the amplified and limited interference waves suitable for full-wave rectification, rectifier means for rectifying the interference energies, and current responsive means governed by the rectified interference energies.

2. In a pulsed continuous Wave reception systern having on and off periods producing alternate spacer and marker intervals, means for producing interference Waves having a component of frequency lower than said continuou wave in the pulsed continuous wave reception system, means adapted to receive both continuous wave and interference energy during the spacer inter vals for detecting the interference wave energies. a square wave amplifier for amplifying and limiting the detected interference energies, inverter tube means for inverting the amplified and limited square wave interference energies into voltages of opposite phases above ground, a fullwave rectifier tube for rectifying the two voltages, and current responsive means controlled by the rectified energies of the rectifier tube.

3. In a pulsed continuous wave reception system having on and off periods producing alternate spacer and marker intervals, means for producing'interference waves having a component of frequency lower than said continuous wave in the pulsed continuous wave reception system, detector means adapted to receive both continuous Wave and interference energy and including means during the marker intervals for neutralizing the pulsed continuous Waves and the interference waves and means during the spacer intervals for detecting and limiting the interference waves having a voltage exceeding a predetermined value, a square wave amplifier for amplifying and limiting the interference waves having a Voltage exceeding a predetermined value, inverter tube means having a push-pull output circuit for rendering the amplified and limited interference waves suitable for full-Wave rectification, rectifier means for rectifying the interference energies, and current responsive means governed by the rectified interference energies.

DONALD L. HINGS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,723,440 Ranger Aug. 6, 1929 2,087,063 McCutchen July 13, 1937 2,276,565 Crosby Mar. 17, 1942 2,283,404 Wood May 19, 1942 2,343,115 Noble Feb. 29, 1944 2,356,224 Crosby Aug. 22, 1944 2,383,126 Hollingsworth Aug. 21, 1945 2,410,843 Shepherd Nov. 12, 1946 Certificate of Correction Patent No. 2,532,667 December 5, 1950 DONALD L. HIN GS It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 7, line 9, strike out the Word second and insert the same in line 10 after a;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Oflice. Signed and sealed this 30th day of January, A. D. 1951.

[SEAL] THOMAS F. MURPHY,

Assistant Oommz'ssz'oner of Patents. 

